billing-economics-source

name

billing-economics-source

description

Keep Companion billing money values tied to source of truth: usage markup/credits in billing economics, and subscription plan prices across plan constants, Autumn/Stripe, RevenueCat, and App Store Connect when Apple IAP is in scope. Load when changing CREDIT_MARKUP, usage credit math, plan prices, top-ups, billing reconcile scripts, RevenueCat/App Store product prices, or paywall price displays. Not for per-plan quota or compute sizing; use tiered-plan-limits.

Billing economics source

Problem this handles

Companion bills users by deducting credits from a usage ledger. A real failure mode is treating UI display math as a second billing model, or spreading markup between worker rates, UI money helpers, Autumn config, and scripts. When the user asks "global 1.25x" or "how does pricing work," answer the source-of-truth model first, then edit.

Subscription price changes have a second failure mode: treating Autumn or the repo constants as the only truth layer after native iOS billing is in scope. A request like "fix all pricing" means web and Apple purchase rails, not only the provider surfaced by the first stale CLI output.

Activation boundary

Load when changing any of these:

• CREDIT_MARKUP, provider raw-cost to credit conversion, or "global 1.25x / 1.5x" pricing behavior.
• src/lib/billing/economics.ts, src/lib/billing/money.ts, worker billing rates, usage ledger writes, billing retry/reconcile scripts, or Autumn credit item values.
• Plan subscription prices, monthly/annual plan amount changes, RevenueCat product/package/entitlement mapping, App Store Connect subscription price schedules, or paywall/store product price displays, including annual savings badges.
• Usage UI, chat credit footer, billing usage tables, or any display that shows credits consumed from usage_events.costMicroCents.

Near-misses:

• Per-plan caps, quotas, storage, vCPU/RAM, or sandbox templates: use tiered-plan-limits.
• Pricing page copy or plan-card marketing without changing billing facts: use product-surface-polish.

Procedure

1. Before editing, state the current model with evidence. For usage economics: raw provider cost is marked up into ledger micro-cents; ledger micro-cents are deducted as credits; UI displays ledger credits. For subscription prices: preserve the user's term for the truth layer and list every rail you will verify before claiming the fix.
2. Read the live source path, not memory:
   • src/lib/billing/economics.ts
   • src/lib/billing/constants.ts
   • workers/agent/lib/billing/rates.ts
   • workers/agent/lib/billing/usage-service.ts
   • autumn.config.ts
   • src/lib/billing/money.ts
   • workers/app/services/usage.ts
   • iOS billing/paywall source and product ID mappings when Apple billing is in scope
   • any UI component or script touched by the requested change
3. Keep the source of truth narrow:
   • CREDIT_MARKUP, ledger unit constants, and credit price constants belong in src/lib/billing/economics.ts.
   • Subscription target prices start in plan constants/config, but live charge truth is provider-specific: Autumn/Stripe for web, App Store Connect for Apple subscriptions, and RevenueCat for product, entitlement, package, and webhook mapping.
   • Apply provider limits at the smallest plan/period scope the evidence proves. An App Store price-point or product-status limit on Max annual disables or changes Max annual only; do not remove annual choices from Plus/Pro or rewrite other rails unless their own records fail the same check.
   • For RevenueCat-backed mobile billing, Autumn receives RevenueCat updates; Autumn prices do not decide the mobile charge.
   • Worker billing code imports economics helpers and writes already-marked-up usage_events.costMicroCents.
   • Autumn tracking uses the same ledger value converted to credits.
   • UI money helpers format ledger values; they must not define markup or estimate raw provider cost unless the surface is explicitly internal and labeled as raw provider cost.
4. For annual price or savings-badge changes, write the arithmetic table before editing: monthly price x 12 baseline, live provider candidate annual prices, exact savings percentage, displayed badge, and the user's rounding rule. "Round percentage" means integer percentage unless the user names another increment; do not invent 5% steps, "conservative" labels, or a lower savings badge when the stated goal is to show the best deal. If no exact common candidate exists across plans, say that before recommending a business fallback.
5. Resolve provider contradictions before mutating. Do not push a catalog or patch code from a summary table when detailed JSON, dashboard UI, or the charge provider disagrees.

Gotchas

• costMicroCents is a deduction amount, not raw provider spend.
• money.ts is a formatter/converter for ledger values. Putting markup there makes UI code look like a billing engine.
• A displayed credit line item should come from the ledger or usage API. Do not recalculate what the user "probably" consumed in the UI.
• Top-up/subscription credit price and provider markup are different knobs: credit price says what a credit costs to buy; markup says how raw provider cost becomes credits consumed.
• App Store subscription prices are configured per country/region in App Store Connect. Check the storefront current price and product status, not only the product ID or RevenueCat offering label.
• Annual savings badges are display claims over a billing value. Compute them from the named monthly baseline and live annual price candidates; do not treat a prettier marketing label as true until the arithmetic is written down.
• RevenueCat entitlements decide access mapping after a purchase; offerings and packages decide what the SDK presents; App Store Connect still owns the Apple subscription price.

Verification

• Run a source grep such as:

rg -n "CREDIT_MARKUP|estimateRawDollars|formatRawDollars|costMicroCents|microCentsToCredits" src workers scripts autumn.config.ts test

• Run focused billing/money tests, then the repo's normal validation for a shared billing change. Report any skipped external mutation explicitly, such as not pushing Autumn config or publishing provider templates.
• For plan-price changes, re-read the live provider records after the change: Autumn detailed product JSON/dashboard for web, RevenueCat product/offering and entitlement mapping for mobile, and App Store Connect subscription price schedules/status for Apple. Name any provider you did not check.

Sources

• Transcript 019ec299 (2026-06-13): user interrupted after a confusing "UI duplicated 1.25 for display math" explanation; follow-up clarified that markup belongs in billing economics and UI should format ledger values.
• Companion src/lib/billing/economics.ts: shared CREDIT_MARKUP, ledger unit constants, and credit price constants.
• Companion workers/agent/lib/billing/rates.ts: raw provider costs are converted to marked-up ledger micro-cents.
• Companion workers/agent/lib/billing/usage-service.ts: usage rows persist costMicroCents and track Autumn credits from that ledger amount.
• Companion src/lib/billing/money.ts: UI money helpers format already calculated ledger values.
• Transcript 019ee099 (2026-06-19): user corrected a "fix all pricing" run because the agent narrowed to Autumn and failed to include Apple/App Store pricing in the named truth layer; later in the same run, the user corrected the agent for turning a Max annual Apple limit into a global no-annual iOS rule, then for choosing annual savings badges without first enumerating the Apple-valid annual price and percent-intersection math.
• Autumn RevenueCat docs: mobile billing is handled through RevenueCat; Autumn receives webhook updates and ignores Autumn prices for RevenueCat purchases.
• Apple App Store Connect docs: auto-renewable subscriptions are priced by country/region in App Store Connect and can be managed through its API.
• RevenueCat entitlements docs: products unlock entitlements, while offerings and packages control what the SDK presents.